QlikView is all it in one!
All you needs can be solved by them (in this case.. :-))
to help you with thouse problems (about the data mart / warehouse).. you only need is creat a new QlikView application and connect to another using QlikView File in your script...(is a button called QlikView File, click and choose a QlikView application)
made a call to another QlikView file to take the data cloud
then if you look to the beginning of the main page, you will see something like this
then reload it!
you can add another tables in the same application, call one or more QlikView application (a don't know how many is the limit).
to conclude, QlikView may be used not only as the best plataform to creat a business intelligence application, but as a integrator between QlikView applications too (as a data smart) or as a warehouse .. where you have a big mounted of data that is divided to some data smart and than showed it with the most powerfull dashboard tools.
I really hope have been helpful, my apology for any mistakes I don't speak english very well